Various approaches to determining device location and/or speed of motion involve the use of signal strength measurements. In some known systems access points (APs), also sometimes referred to as base stations, transmit known radio signals, e.g., beacon and/or pilot signals at a known transmit power level. A device, e.g., a user equipment device (UE) in an area where the APs transmit can measure the power of the received signals, which were transmitted at a known power level from a known location and transmitter. The power level of signals received from APs can then be used by the UE to determine its location and/or the received signal strength information can be reported to another device for use in determining the location of the UE.
Such an approach relies on the ability of UE devices to receive signals and use the received signal strength information and/or report the received signal strength information to another device for location determination purposes.
Low cost beacon transmitters which transmit a known signal at a known power level are becoming more common. Such devices normally don't include a receiver and rather than receiving and reporting the strength of a beacon or other signal transmitted by an AP simply transmit a known signal which can be used to identify the device transmitting the signal.
Various attempts to determine the location of low cost beacon transmitters and the use location information that can be generated from the receipt of signals transmitted by such devices have been made.
While the measurement of signals received from devices transmitting beacons at a known power level for location determination might seem straight forward, device movement and/or changes in an environment may, and often do, affect the strength of signals received from such devices. Since inexpensive beacon transmitter devices normally only transmit a beacon or other fixed signal and do not transmit information expressly indicating whether or not they are moving, motion information is normally not readily available to a device receiving signals from a beacon transmitter device.
In view of the above it should be appreciated that there is a need for methods and/or apparatus for determining when a device transmitting beacon or other signals is in motion, processing signals received from devices, taking into consideration whether or not they are in motion, and/or taking into consideration motion information when making a decision when or how location information generated from signals received from a device should be used.